Diet and the Brain

Contributed by: Dennis Fortier, President, Medical Care Corporation

On the one hand, we all know intuitively that our diet effects the way we feel. Many of us feel tired after a heavy meal, many of us are irritable when hungry, and many of us are familiar with the boost/crash cycle of eating sugary snacks. Most would also agree that a light, nutritious meal makes us feel differently than one based on junk food.

On the other hand, many claims about certain foods and their impact on brain health, have been either overblown or misinterpreted by the masses. As far as we know, there is no particular oil, berry, fish, root, herb, or vegetable that we should all start consuming in massive quantities, as a means to an immediate improvement in brain function.

Rather, it is important to think about diet and the brain in both the short term and the long term. This is true because dietary habits have both short-term and long-term effects on the brain. Guidelines for a healthy brain diet have been discussed here and elsewhere many times.

The point of today's post is to emphasize the importance of the word "habit" in the phrase "dietary habit". If you consistently consume a lot of preservative filled, sugar laden, trans fat based snacks, you can't undo the damage with a giant bowl of spinach and a glass of fish oil. Despite claims you may read about coconut oil, green tea, and gingko biloba, don't fool yourself into thinking that you can add those elements to a poor diet and your brain will be fine.

Can Blood Pressure Drugs Prevent Alzheimer's?

Contributed by: Dennis Fortier, President, Medical Care Corporation

If you only read the headlines, and not the news beneath those headlines, you might be inclined to think that a certain class of blood pressure medications (angiotensin receptor blockers) can prevent Alzheimer's disease.

A recent publication in Archives of Neurology has spawned a number of sensational headlines about Alzheimer's prevention.  The study showed that, among nearly 900 subjects who died at old age and had brain autopsies, those who had taken angiotensin receptor blockers had fewer amyloid plaques in their brains.  This was true of patients with Alzheimer's disease, patients with other causes of dementia, and patients with normal cognitive health.

Amyloid plaques in the brain are a hallmark sign of Alzheimer's disease, but it is not yet well understood if the plaques are the cause of the disease, or if they are a protective response by the brain against some other biological process.  For this reason, it would be a great leap to suggest that blood pressure drugs could play a role in treating Alzheimer's disease.  While that might be true, it is equally possible that such drugs could play a role in preventing the body's natural attempt to protect itself from other facets of the disease process.

Every new clue is useful in assembling the big picture and understanding this complex disease.  This study yielded a great finding, an interesting correlation, and the possibility of new insights. But as far as we know, it did not uncover a preventative treatment for Alzheimer's disease.

New Generation Alzheimer's Drugs: Do They Work?

Contributed by: Dennis Fortier, President, Medical Care Corporation

We've all been hopeful that a new class of Alzheimer's drugs (monoclonal antibodies) would soon bring effective treatment to the growing number of Alzheimer's patients.

The latest approach is based on using antibodies that bind with harmful amyloid protein.  The idea is that the antibodies will be naturally flushed from the body by the immune system, and take the harmful amyloid away as well.

Major trials have now concluded on two such drugs: Bapineuzumab and Solanezumab.  The primary outcome measures of these trials were "improved cognition" and/or "improved function" versus a placebo group.  That is to say, if subjects who took these drugs had either better cognition or better physical ability to perform daily activities, compared to subjects who did not, then the drugs were probably effective enough to be approved by the FDA. On these measures, all trials have failed.

But that is not necessarily the end of the story for either drug.

A secondary analysis, performed on a combination of the data from the multiple Solanezumab trials, shows a small improvement in cognition among treated subjects.  It is a weak signal, but it provides some hope on which to build.  Especially noteworthy is that the positive effect was most evident in the earlier stage patients with healthier brains.

A stronger signal has come from a look at the targeted biomarkers (amyloid and tau proteins) that these drugs target.

Researchers have speculated (and common sense has suggested), that using such drugs to remove amyloid from the brains of subjects who have already suffered a fair amount of brain damage, may not be helpful.  The obvious experiment would be to remove the amyloid at an earlier stage, before brain damage occurs, which is before symptoms of memory loss and other cognitive decline are noted. This makes intuitive sense and is well-aligned with the possible effect detected in the Solanezumab trial on early stage subjects.

As such, a key indictor of the true potential for each drug may be actual measures of amyloid reduction in those subjects who were treated.  Researchers involved in the Bapineuzumab trial announced yesterday that the drug did in fact dramatically reduce amyloid in the brain and spinal fluid of trial subjects.  Similar biomarker data from the Solanezumab trial is expected in the coming weeks.

Overall, we wish that the drugs had produced great improvements in cognition and function.  While those goals were not met, it is encouraging to note that some, small measure of cognitive improvement may have been realized in the Solanezumab trials, and a clear reduction in amyloid protein was seen in the Bapineuzumab trials.

This leaves us with a hopeful hypothesis that, if used on subjects at an earlier stage of Alzheimer's disease, before extensive brain damage has occurred,  either or both drugs may yield more effective treatment than what is currently available.